Some is not even made from the Mexican vanilla beans.  Many Mexican vanillas start with pure vanilla extract as the base.  This is then watered down with glycerin, or water.  Then it is fortified with synthetic vanilla, caramel coloring, sugar or corn-syrup, and other natural flavors.  Wow, no wonder it is so cheap!  There's almost no pure vanilla extract in it!  It does smell and maybe even taste pretty good, until the bitter synthetic vanilla aftertaste kicks in.  I'm not saying that these Mexican vanillas won't work, or doesn't necessarily taste good in your recipes; it's just that there is a better product…pure vanilla extract made from real Mexican vanilla beans.  Accept no substitute. You will not be disappointed.